x86, vdso: Fix size of get_unmapped_area()

The size of the reserved memory for a 32 bit vdso must be the size of the
32 bit vDSO in pages + HPET page + VVAR page.

One page is not enough for this. Grrrr.... silly copy and paste bug,
was right in previous patch.

Signed-off-by: Stefani Seibold <stefani@seibold.net>
Cc: Andy Lutomirski <luto@amacapital.net>
Link: http://lkml.kernel.org/r/1395592694-20571-1-git-send-email-stefani@seibold.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/vdso/vdso32-setup.c

@@ -165,12 +165,14 @@ int arch_setup_additional_pages(struct linux_binprm *bprm, int uses_interp)
 
 	down_write(&mm->mmap_sem);
 
-	addr = get_unmapped_area(NULL, 0, PAGE_SIZE, 0, 0);
+	addr = get_unmapped_area(NULL, 0, vdso32_size + VDSO_OFFSET(VDSO_PREV_PAGES), 0, 0);
 	if (IS_ERR_VALUE(addr)) {
 		ret = addr;
 		goto up_fail;
 	}
 
+	addr += VDSO_OFFSET(VDSO_PREV_PAGES);
+
 	current->mm->context.vdso = (void *)addr;
 
 	/*